Jefferson Medical College is submitting a competing renewal to the "Cooperative Multicenter Maternal-Fetal Medicine Units Network" RFA HD-00-009. Jefferson has been an active and productive participant in the Maternal-Fetal Medicine Units Network (MFMU) over the last four years. The Jefferson Center (JC) has actively recruited for all MFMU protocols and has routinely been among the top centers in patient recruitment,data accuracy, and data reliability. The JC P.I. is chairman of both the steroid and the genetics subcommittees. Its faculty and staff has participated on subcommittees, introduced concepts, participated in Steering Committee meetings, and performed secondaryanalysis of data. The JC provides the Network with over 8,700 deliveries per year of which over 35% are high-risk. All patients are available to participate in trials. The JC has a faculty of 20 Maternal-Fetal Medicine subspecialists with 6 designated physicians having primary responsibilityfor Network activity. These physicians have adequate protected time. Jefferson has an academic, research environment demonstrated by its Network participation to date, participation in other multicenter trials, and existence of an extensive research infrastructure. There are intrapartum and antepartum facilities for research recruitment, hospital staffs experienced in research participation, and a large research staff (I Nurse| Coordinator, 3 Masters nurses, 6 R.N.s, 2 Research Associates, a full-time Data Base Manager, and a Data Entry Clerk),j The JC has a large, academic, neonatal service with 1,874 neonates cared for per year by 23 full-time neonatologi>i.s. I The neonatal unit is submitting an application for participation in the Neonatal Network. The JC offers the Network- additional expertise in clinical and molecular genetics, ultrasound,and epidemiology.Administrative strengths include a large organized perinatal network (>30,000 births per year) providing additional patients when required. The JC has proposed a concept on the timing of cervical cerclage removal following preterm premature rupture of the membranes.! The supporting documentation for this prospective randomized trial demonstratesthe Center's research acumen as well as the breath and strength of the data base. The JC is strongly committed and prepared to continue active participation in the MFMU.